JP2000347362A - Black-and-white development/fixing monobath composition, image forming method and processing kit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively and efficiently process the black-and-white photographic element low in a silver amount in the development/fixing monobath solution. SOLUTION: This black-and-white photographic element low in a silver amount is processed by using the black-and-white develment/fixing aqueous monobath solution having a pH of 10-12.5, and not containing a dihydroxybenzene developing agent and an ammonium ion but an ascorbic acid developing agent in an amount of 80-200 mmol/L and at least 200 mmol/L sulfite ions and as a sole photographic fixing agent an organic fixing agent having both of a thiol group and an amino group in an amount of 40-300 mmol/ L.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

FIELD OF THE INVENTION The present invention relates generally to photography, and more particularly to an improved method of processing black and white photographic elements. More particularly, the present invention relates to a method of processing low silver content radiographic films, as well as developing / fixing compositions useful therein.

[0002]

X-rays have discovered X-rays by the inadvertent exposure of silver halide photographic elements. 1913
Year, Eastman Kodak Introduces First Product for X-Ray Exposure
No. announced. Silver halide radiographic films account for an overwhelming majority of medical diagnostic images. Soon, high-energy ionizing x-rays were potentially harmful, and the search for ways to increase patient exposure was recognized. Radiographic films provide an observable silver image by a rapid access process following imagewise exposure.

One method, which is still widely used, is to coat a silver halide emulsion useful for radiographic films on both sides of a film support. Therefore, the X-ray dose that can be absorbed and used for image formation is 2
Twice as high and higher sensitivity can be obtained. Double-coated radiographic film from Eastman Kodak DUPLITIZ
It is marketed under the trade name of ED film. In the art, films that rely entirely on X-ray absorption for image capture are termed "direct" radiographic elements, while films that rely on intensifying screen emission are termed "indirect" radiographic elements. I have.

[0004] Direct radiographic films capture X-rays during imaging, but for some reason (eg,
There are other uses, such as in the case of welds of pipelines and turbine blades), various industrial uses where intensifying screens cannot be used. It is widespread to process a radiographic film through a black-and-white developing step, a fixing step, a washing step and a drying step. The film processed in this way is ready for image observation.

[0005] In the photographic art, photographic black-and-white developing compositions containing a silver halide black-and-white developing agent for reducing silver halide grains containing a latent image to obtain photographic development are well known. Many useful developing agents are known in the art, the most common being hydroquinone and similar dihydroxybenzene compounds and ascorbic acid (and derivatives). Such compositions generally also include other ingredients such as sulfites, buffers, antifoggants, halides and hardeners.

[0006] Fixing compositions for radiographic films are also well known and include one or more fixing agents, among which thiosulfates are the most common. Such compositions generally include a sulfite as an antioxidant. US Patent No. 5,800,976 (Dickerson et al.)
Describe radiographic elements having low silver coverage and containing specific covering power enhancing compounds within the silver halide emulsion. However, such elements are generally processed in conventional developing compositions containing hydroquinone or other dihydroxybenzene compounds. Such developing compositions are undesirable because they have a negative impact on the environment.

[0007] "Mono bath" solutions are also known in the photographic processing field. These solutions typically require long processing times and contain a component common to both developing and fixing compositions, namely sulfites, and have a high pH. It has been difficult to achieve an acceptable development process using the monobath solution. Because the fixation was too quick (and therefore D
_max is too low), because the fog (D _min is high), or fixing agent or is too small, the fixing time or hardly occurred fixing to or insufficient. It is difficult to achieve the desired balance between all conditions and sensitometric results. Either a very long processing time is required or the silver removal is too high and the density is too low. These concerns are exacerbated when the radiographic element to be processed contains less than normal silver coverage.

[0008]

SUMMARY OF THE INVENTION The above problems have been solved,
There is a need for processing methods and monobass compositions that can provide an acceptable black and white image in an environmentally acceptable manner in a short time.

[0009]

SUMMARY OF THE INVENTION The above-mentioned objects are as follows.
Has a pH of 2.5, contains no dihydroxybenzene developing agent and ammonium ions, and
L to 200 mmol / L ascorbic acid developing agent, at least 200 mmol / L sulfite ion, and as a single photographic fixing agent, 40 mmol / L to 300 mmol / L organic compound having both thiol group and amino group Is overcome by using an aqueous black-and-white developing / fixing monobass composition comprising

The present invention is also a method for providing a black-and-white image comprising the step of contacting an imagewise exposed black-and-white photographic silver halide element with the aqueous black-and-white developing / fixing monobass composition. The method is carried out within a maximum of 180 seconds, and prior to said contacting step, said black-and-white photographic silver halide element comprises a silver halide emulsion comprising silver halide grains and a gelatin-based vehicle on each side of its support. A unit is arranged, and the silver halide grains are composed of bromide in an amount of 95 mol% or more based on the total silver.
At least 50% of the projected area of the silver halide grains is occupied by tabular grains having an average aspect ratio higher than 8, a thickness of 0.10 μm or less, and an average grain size in the range of 1.5 to 3 μm. Wherein the silver coverage in each silver halide emulsion unit is 11 mg / dm ² or less, and the gelatin vehicle in each silver halide emulsion unit is 11 mg / dm ² or less. Give a way to do it.

The present invention provides an effective and efficient means of processing low silver content black and white photographic elements in a manner that reduces their environmental impact. Known processing of higher silver radiographic elements results in too fast fixing or too low a resulting _Dmax . When a monobath composition containing a large amount of a black-and-white developing agent is used, fogging (high D _min ) occurs or time or fixing agent is insufficient, so that fixing hardly occurs. It is difficult to balance all of the competing needs and sensitometric properties of a radiographic element with a monobass composition. These problems are particularly noted in the processing of black-and-white silver halide elements containing relatively little silver.

As used herein, a “monobass” composition includes:
It is meant to describe a processing composition that has both photographic black-and-white development properties and fusing properties. Surprisingly, it has been found that the monobass composition of the present invention overcomes the above-mentioned problems. In particular, it was surprising to be able to provide the desired image property balance using cysteine and similar compounds as photographic fixing agents at lower fixing concentrations in combination with "weaker" ascorbic acid black and white developing agents. Thus, black-and-white development is satisfactorily initiated and fusing is completed within a preferred reduced processing time. Due to the avoidance of "stronger" dihydroxybenzene developing agents and ammonium ions, this monobass composition has little environmental impact when released.

These advantages are achieved by the unique combination of a low silver content silver halide element and a unique monobass processing composition. The monobass composition of the present invention combines a black and white developing agent and a particular photographic fixing agent into a single, simple composition having the appropriate composition concentration and pH to provide all of the desired characteristics. The photographic fixing agent used in the present invention is
It has both a thiol group and an amino group. A particularly useful photographic fixing agent is cysteine.

Due to the combination of the above features, the development process can be achieved in a relatively rapid manner. Because the element has less than normal silver and binder coverage, the processing solution can diffuse quickly into the element, cause the desired chemical reaction, and remove unwanted silver.

[0015]

DETAILED DESCRIPTION OF THE INVENTION The present invention is useful in providing black-and-white images in photographic silver halide elements, preferably in radiographic films having low silver halide content. Other types of elements that can be processed using the present invention include aerial photography films, black and white motion picture films, duplicating and duplicating films, and amateur and professional continuous tone black and white films with silver halide coverage. There are few things,
It is not limited to these. While the general composition of such materials is well known in the art, specific features that make them particularly suitable for the present invention are described in further detail below.

The black-and-white developing / fixing monobass composition of the present invention contains one or more black-and-white developing agents that are not dihydroxybenzene or a derivative thereof. Rather, this developing agent is what is known as "ascorbic acid-based developing agent" meaning ascorbic acid and its derivatives.

Ascorbic acid based developing agents are described in a number of photographic processing publications, including US Pat. No. 5,236,816 (Purol et al.) And the references cited therein. Useful ascorbic acid-based developing agents include ascorbic acid and its analogs, isomers and derivatives. Such compounds include D- or L
-Ascorbic acid, its sugar derivative (eg, sorbascorbic acid, γ-lactoascorbic acid, 6-desoxy-
L-ascorbic acid, L-rhamnoascorbic acid, imino-6-desoxy-L-ascorbic acid, glucoascorbic acid, fukoascorbic acid, glucoheptoascorbic acid, maltoascorbic acid, L-arabosascorbic acid), ascorbic acid Sodium, potassium ascorbate, isoascorbic acid (or L-erythroascorbic acid) and its salts (eg, alkali metals, ammonium and others known in the art), enediol-type ascorbic acid, enaminol-type ascorbic acid, thioenol Ascorbic acid as well as enamine-thiol ascorbic acid. These compounds are described, for example, in US Pat.
No. 8,511 (Yamashita et al.), European Patent Application Publication No. 058
No. 5792 (issued March 9, 1994), No. 0
573 700 (issued December 15, 1993),
No. 0 588 408 (issued March 23, 1994)
), International Publication No. WO95 / 00881 (issue date 19
U.S. Pat. Nos. 5,089,819 and 5,278,035 (both Knapp) and 5,
No. 384,232 (Bishop etc.), No. 5,376,51
No. 0 (Parker, etc.) and JP-A-7-56286 (issue date 1
March 3, 995), U.S. Patent Nos. 2,688,549 (James et al.), 5,236,816 (supra), and Research Disclosure.
e, 37152, March 1995). D-, L-
Or, D, L-ascorbic acid (and their alkali metal salts) or isoascorbic acid (or their alkali metal salts) is preferred. Most preferred are sodium ascorbate and sodium isoascorbate. If desired, mixtures of these developing agents can be used.

The developing / fixing monobass composition is also known as one or more auxiliary developing agents (eg, Mason, Photographic Processing Chemistr).
y, Focal Press, London, 1975). Although any auxiliary developing agent can be used, the preferred one is 3
-Pyrazolidone-based developing agents (also known as "phenidone" -based developing agents). Such compounds are described, for example, in US Pat. No. 5,236,816 (supra).
It is described in. The most commonly used compounds of this type are 1-phenyl-3-pyrazolidone,
1-phenyl-4,4-dimethyl-3-pyrazolidone,
4-hydroxymethyl-4-methyl-1-phenyl-3
-Pyrazolidone, 5-phenyl-3-pyrazolidone, 1
-P-aminophenyl-4,4-dimethyl-3-pyrazolidone, 1-p-tolyl-4,4-dimethyl-3-pyrazolidone, 1-p-tolyl-4-hydroxymethyl-4
-Methyl-3-pyrazolidone and 1-phenyl-4,4
-Dihydroxymethyl-3-pyrazolidone. Other useful auxiliary developing agents are described, for example, in US Pat.
No. 7,434 (Roussihle et al.), Such as a sulfo, carboxy or hydroxy group attached to an aliphatic chain or an aromatic ring, preferably to the hydroxymethyl function of pyrazolidone. Contains one or more solubilizing groups. The most preferred auxiliary developing agent is 4-hydroxymethyl-4-methyl-1-phenyl-3-pyrazolidone.

Less preferred auxiliary developing agents are aminophenols such as p-aminophenol,
o-aminophenol, N-methylaminophenol,
2,4-diaminophenol hydrochloride, N- (4-hydroxyphenyl) glycine, p-benzylaminophenol hydrochloride, 2,4-diamino-6-methylphenol,
2,4-Diaminoresorcinol and N- (β-hydroxyethyl) -p-aminophenol. If desired, mixtures of different auxiliary developing agents can also be used.

The developing / fixing monobath composition of the present invention includes:
It is also preferred that the organic antifoggants be present alone or as a mixture. Such compounds control the net fog appearance in the treated element. Suitable antifoggants include, but are not limited to, benzimidazole, benzotriazole, mercaptotetrazole, indazole and mercaptothiadiazole. Representative antifoggants include 5-nitroindazole, 5-p-nitrobenzoylaminoimidazole, 1-methyl-5-nitroindazole, 6-nitroindazole, 3-methyl-5-nitroindazole,
5-nitrobenzimidazole, 2-isopropyl-5
-Nitrobenzimidazole, 5-nitrobenzotriazole, sodium 4- (2-mercapto-1,3,4-thiadiazol-2-yl-thio) butanesulfonate,
5-amino-1,3,4-thiadiazol-2-thiol, 5-methylbenzotriazole, benzotriazole and 1-phenyl-5-mercaptotetrazole. Most preferred is benzotriazole.

The developing / fixing monobass composition further contains one or more preservatives or antioxidants. Various common black-and-white preservatives such as sulfites can be used. As used herein, "sulfite" preservative means any sulfur compound capable of producing or providing sulfite ions in an aqueous alkaline solution. Examples include alkali metal sulfites, alkali metal bisulfites,
Examples include, but are not limited to, alkali metal metabisulfites, amine sulfur dioxide complexes, sulfurous acid, and carbonyl-bisulfite adducts. Mixtures of these materials can also be used.

Examples of suitable sulfites include sodium sulfite, potassium sulfite, lithium sulfite, sodium bisulfite, potassium bisulfite, sodium metabisulfite,
Potassium metabisulfite and lithium metabisulfite are included. Useful carbonyl-bisulfite adducts include alkali metal or amine bisulfite adducts of aldehydes and bisulfite adducts of ketones. Examples of these compounds include formaldehyde sodium bisulfite,
Examples include sodium acetaldehyde bisulfite, succinaldehyde disodium bisulfite, acetone sodium bisulfite, β-methylglutaraldehyde disodium bisulfite, butanone sodium bisulfite and 2,4-pentanedione disodium bisulfite.

The composition may contain various known buffers such as carbonates and phosphates to maintain the desired pH. pH is a suitable base (eg hydroxide)
Alternatively, it can be adjusted with an acid. P of developing / fixing composition
H is preferably from 10 to 12.5, more preferably 1
It is in the range of 0.5 to 12.

The developing / fixing monobass composition must also contain a photographic fixing agent which is one or more organic compounds. Each compound has both a thiol group and an amino group ("thiol / amino anchoring agent"). Examples of such organic compounds include cysteine, methionine, thiourea, thiosemicarbazone and mercaptopyrimidine. If desired, mixtures of these fixing agents can also be used. In a preferred embodiment, cysteine is used alone. Apart from this class of organic compounds, the compositions do not contain other photographic fixing agents.

Optionally, the developing / fixing compositions of the present invention commonly employ sequestering agents whose typical function is to form a stable complex with free metal ions (eg, silver ions) in solution. One or two or more kinds are contained in the amount. Although many useful sequestering agents are known in the art, a particularly useful class of compounds is disclosed in US Pat.
No. 389,502 (Fitterman et al.), Including, but not limited to, multimeric carboxylic acids, aminopolycarboxylic acids, polyphosphate ligands, ketocarboxylic acids and alkanolamines. Representative sequestering agents include ethylenediaminetetraacetic acid, diethylenetriaminepentaacetic acid, 1,3-propylenediaminetetraacetic acid, 1,3-diamino-2-propanoltetraacetic acid, ethylenediaminodisuccinic acid and ethylenediaminomonosuccinic acid Is included.

Further, the developing / fixing monobass composition is
Other additives such as various development inhibitors, development accelerators, swelling control agents and stabilizers can also be contained in conventional amounts. For specific examples of such optional components, see US Pat. No. 5,236,816 (above) and US Pat. No. 5,474,879 (Fitterman).
Etc.), JP-A-7-56286 and EP-A-0 585 792.

The developing / fixing monobath composition is essentially free of ammonium ions. This means that no ammonium ions are intentionally added and the only ammonium ions present are leached as impurities or from the element to be treated. Thus, the salts used in the compositions will generally be in the form of potassium or sodium salts.

The above-mentioned essential components (and some optional components)
Is present in the aqueous developing / fixing monobath composition in the general and preferred amounts listed in Table I below. In Table I, both the lower and upper limits are approximate amounts (ie,
"About"). When formulated in dry form, the developing composition will include the essential components in amounts obvious to those skilled in the art and suitable to provide the desired liquid concentration.

[0029]

[Table 1]

The developing / fixing monobass composition is prepared by dissolving or dispersing the components in water and adjusting the pH to a desired value. Alternatively, the composition may be provided in a concentrated form and diluted to the working concentration immediately before or during use. The components of the composition can also be provided as a two or more part kit to be mixed and diluted to the desired concentration with water before being placed in a processing device as a monobath composition.

Processing can be carried out in any suitable processor or processing vessel for certain photographic elements. For example, in the case of a radiographic film, the method can be carried out using one or more containers for carrying out development and fixing together. In most cases, the element being processed is a film sheet, but this may be a continuous element. Each element is immersed in the monobath composition for an appropriate time in each step.

Following the development / fixing step, preferably, but not necessarily, an appropriate washing step is performed to remove silver salts and excess fixing agent dissolved by fixing and reduce swelling of the element. The washing solution may be water, but preferably with a suitable acid chemical or buffer to make the washing solution acidic, more preferably its pH is below 7, preferably in the range of 4.5-7. After washing, the treated elements can be dried for a suitable time and temperature, but in some cases, the black and white image can be observed in a wet state. The processing times and conditions of the present invention are listed in Table II below. In Table II, both the lower and upper limits are approximate (ie, "about"). The total time required to carry out the method of the invention is generally 30
Seconds or more, preferably 45 seconds or more and generally 18
It is less than 0 seconds, preferably less than 120 seconds.

[0033]

[Table 2]

The black-and-white photographic silver halide elements processed according to this invention generally comprise one or more photographic silver halide emulsion layers on each side of a conventional flexible transparent film support (polyester, cellulose acetate or polycarbonate). Is applied. In the case of radiographic films, it is customary to use a bluish support material to contribute to the blue-black image gradation required for a fully processed film. Polyethylene terephthalate and polyethylene naphthalate are preferred film supports.

In general, such elements, emulsions and layer compositions are described in Research Disclosu
re, 36544, September 1994). Research Disclosure is from Kenneth Mason Publications, Ltd. (Dudley Hous
e, 12 North Street, Emsworth, Hampshire PO10 7DQ E
ngland).

The emulsion layer contains a photosensitive high silver bromide for image formation. To facilitate rapid access processing, it is preferred that the iodide contained in the grains is less than 2 mole percent, based on total silver. The silver halide grains are mainly composed of silver bromide. That is, the particles are silver bromide,
It can be composed of silver iodobromide, silver chlorobromide, silver iodochlorobromide or silver chloroiodobromide, provided that the bromide content is 95 mol% or more (preferably 98 mol%) based on the total silver content. % Or more).

In addition to the benefits obtained by the above composition selection,
The use of silver halide grains having a coefficient of variation (COV) of the grains ECD of less than 20%, preferably less than 10%, is specifically contemplated. It is preferable to use a particle population that exhibits high monodispersity within a range that can be appropriately realized. Furthermore, 50% or more (preferably 70%) of the projected area of the silver halide grains.
Above) are occupied by tabular grains having an average aspect ratio higher than 8, preferably higher than 12. The average thickness of the particles is generally 0.06 μm or more and 0.10 μm
Or less, preferably 0.07 μm or more and 0.09 μm or less. The average particle size is in the range 1.5-3 μm, preferably in the range 1.8-2.4 μm.

Tabular grain emulsions meeting the requirements for high bromide grains and the requirements for gelatinous vehicles, except that the gelatinous vehicle is completely forehardened, are described in detail in the following patent specifications. U.S. Pat. No. 4,414,310 (Dickerson) U.S. Pat. No. 4,425,425 (Abbott et al.) U.S. Pat. No. 4,425,426 (Abbott et al.) U.S. Pat. No. 4,439,520 (Kofron et al.) U.S. Pat. No. 4,434,226 (Wilgus et al.) U.S. Pat. No. 4,435,501 (Maskasky) U.S. Pat. No. 4,713,320 (Maskasky) U.S. Pat. No. 4,803,150 (Dickerson et al.) U.S. Pat. No. 4,900,355 (Dickerson et al.) U.S. Pat. No. 4,994,355 (Dickerson et al.) U.S. Pat. No. 4,997,750 (Dickerson et al.) U.S. Pat. No. 5,021,327 ( Bunch et al.) U.S. Pat. No. 5,147,771 (Tsaur et al.) U.S. Pat. No. 5,147,772 (Tsaur et al.) U.S. Pat. No. 5,147,773 (Tsaur et al.) U.S. Pat. No. 5,171,659 No. 5,252,442 (Tsaur et al.) U.S. Pat. No. 5,391,469 (Dickerson) U.S. Pat. No. 5,399,470 (Dickerson et al.) U.S. Pat. No. 5,411,853 (Maskasky) U.S. Pat. No. 5,418,125 U.S. Pat. No. 5,494,789 (Daudendiek et al.) U.S. Pat. No. 5,503,970 (Olm et al.) U.S. Pat. No. 5,536,632 (Wen et al.) U.S. Pat. No. 872 (King et al.) US Pat. No. 5,567,580 (Fenton et al.) US Pat. No. 5,573,902 (Daudendiek et al.) US Pat. No. 5,576,156 (Dickerson) US Pat. No. 5,576 U.S. Pat. No. 5,576,171 (Olm et al.) U.S. Pat. No. 5,582,965 (Deaton et al.) Gelatin-based vehicles, high bromide tabular grain emulsions and other important aspects of the present invention. Show features of common elements in addition to features For this purpose, reference is made to the patent specifications of Abbott et al., Fenton et al., Dickerson and Dickerson et al.

The contrast of the film can be increased by introducing one or more contrast enhancing dopants. It is well known that rhodium, cadmium, lead and bismuth all enhance contrast by inhibiting foot development. Cadmium is toxic and its continuous use has been ruled out. Rhodium is most commonly used for contrast enhancement and is particularly preferred. The concentration that enhances the contrast is Ag
It is known to be in the range from as low as 10 ^-9 mole per mole. Rhodium concentrations of up to 5 × 10 ⁻³ mole per mole of Ag are specifically contemplated. A particularly preferred addition amount of rhodium is 1 × 10 ^-6 to 1 per mol of Ag.
× 10 ^-4 mol.

Other various dopants are individually
It is also known in combination to improve contrast and other general properties, such as photographic sensitivity and reciprocity properties. Specifically, dopants (commonly referred to as SET dopants) that can provide "shallow electron trap" sites are contemplated. For research on SET dopants, please refer to Research Disclosur.
e, Vol. 367, Nov. 1994, Item 36736). Iridium dopants are very commonly used to reduce reciprocity failure. For an overview of common dopants for improving photographic speed, reciprocity and other imaging characteristics, see the Research Disclosure, Item 36544 section above.
I. Emulsion grains and their preparation, subsection D. Grain modifying conditions and adjustm
ents, described in paragraphs (3), (4), (5).

An emulsion having a low COV can be selected from emulsions prepared by a conventional batch double jet precipitation method. For an overview of silver halide emulsions and their preparation, see Research Disclosure (Researc
h Disclosure, Item 36544) section I. Emulsion
It is described in grains and their preparation. After the precipitation step and prior to chemical sensitization, it may be washed by any suitable conventional technique using the techniques described in Research Disclosure, Item 36544, supra, Section III. Emulsion washing.

The emulsion was prepared by Research Disclosure (R
esearch Disclosure, Item 36544) section IV. Ch
Chemical sensitization can be carried out by any of the conventional and appropriate methods described in emical sensitization. Specifically, sulfur sensitization and gold sensitization are contemplated.

Both silver bromide and silver iodide show significant intrinsic sensitivity in the blue part of the visible spectrum. For this reason, when the bromide concentration of the emulsion grains is high (> 50 mol% based on the total silver), spectral sensitization of the grains is not necessary, but it is preferable to perform the sensitization. Specifically, it is contemplated that one or more spectral sensitizing dyes may be adsorbed on the surface of the particles to impart or enhance the photosensitivity of the particles. Ideally, the maximum absorption region of the spectral sensitizing dye is matched to the main emission band (s) of the fluorescent intensifying screen (eg, within a range of ± 10 nm). In fact, any spectral sensitizing dye may be used for the first radiographic film, as long as it shows a half-maximum absorption width that overlaps with the main spectral region of light emission by the fluorescent intensifying screen intended for use after coating. it can.

As conventional spectral sensitizing dyes, the absorption maximum is in the near ultraviolet region (300 to 400 nm), visible region (400 to 700 nm) and near infrared region (700 to 400 nm) of the spectrum.
A wide variety covering the entire range (1000 nm) is known. Specific examples of commonly used spectral sensitizing dyes include Research Disclosure, Item 18
431) section X. Spectral sensitization and Research Disclosure, It
em 36544) section V. Spectral sensitization a
nd desensitization, A. Sensitizing dyes.

The instability (ie, fog) that raises the minimum density in the coating of negative working emulsions is due to the stabilizer,
Anti-fogging, anti-kinking, latent image stabilizers and similar additives can be prevented by including them in the emulsion and adjacent layers prior to coating. Such additives are described in Research Disclosure (Research Disc).
losure, Item 36544) section VII. Antifoggants
and stabilizers and Research Disclosure (R
esearch Disclosure, Item 18431) Section II. E
mulsion Stabilizers, Antifoggants and Antikinking
Agents.

The silver halide emulsion preferably also contains one or more covering power enhancing compounds adsorbed on the surface of the silver halide grains. Although several such materials are known in the art, suitable covering power enhancing compounds contain one or more divalent sulfur atoms that can take the form of -S- or = S moieties. I do. Such compounds include 5-mercaptotetrazole, dithioxotriazole, mercapto-substituted tetraazaindene, and other U.S. Pat.
No. 0,976 (above), but are not limited thereto. Such compounds are generally present in a concentration of 20 mg or more, preferably 30 mg or more, per mole of silver. This concentration is generally 2 moles per silver mole.
The concentration can be as high as about 000 mg, preferably about 700 mg.

Further, it is also preferred that the silver halide emulsion on each side of the support contains dextran or polyacrylamide as a water-soluble polymer which can also enhance the covering power. These polymers are generally present in a weight ratio to the gelatin-based vehicle (described below) of at least 0.1, preferably in the range of 0.3 to 0.5.
Dextran or polyacrylamide up to 5mg
/ Dm ^2, preferably can be present in an amount in the range of 2-4 mg / dm ^2. The amount of covering power enhancing compound may be the same or different on both sides of the support.

The silver halide emulsion and other layers which form the image-forming units on both sides of the support of the radiographic element are typically gelatin or a gelatin derivative (referred to herein as "gelatin-based vehicles"). Containing conventional hydrophilic colloid vehicles (peptizers and binders). For the characteristics of conventional gelatin-based vehicles and related layers, see Research Disclosure (Resea
rch Disclosure, Item36544) section II. Vehicl
es, vehicle extenders, vehicle-like addenda and ve
It is described in hicle related addenda. The emulsion itself is described in paragraph A. Gelatin and hydro
Peptizers of the type described in the hydrophilic colloid peptizers may be included. Since the hydrophilic colloid peptizer is also useful as a binder, it is generally present at a concentration much higher than the concentration required to exert only the peptizing effect. Gelatin-based vehicles also include materials that are not themselves useful as peptizers. Suitable gelatin-based vehicles include alkali-treated gelatin, acid-treated gelatin or gelatin derivatives (eg, acetylated gelatin and phthalated gelatin).

In order to be able to meet the highest density requirements with the lowest silver coverage, it is necessary to limit the forehardening of the gelatinous vehicle. While it is customary for radiographic elements containing tabular grain emulsions to be fully forehardened, the radiographic elements of this invention are only partially forehardened. Therefore, the amount of hardener contained in each silver halide emulsion unit is generally 0.1% or more and less than 0.8%, preferably 0.3% or more and 0.8% or less, based on the total dry weight of the gelatin-based vehicle. The range is less than 6%.

For this purpose, customary hardeners can be used. Such hardeners include formaldehyde and free dialdehydes such as succinaldehyde and glutaraldehyde, blocked dialdehydes, α-diketones, active esters, sulfonic esters, active halogen compounds, s-triazines and diazines, epoxides , Aziridine, active olefin having two or more active bonds, blocked active olefin, carbodiimide, 3-position unsubstituted isoxazolium salt, 2-alkoxy-N-carboxydihydroquinoline, N-carbonylpyridinium salt, carbamoyloxypyridinium salt, Bis (imoniomethyl) ether salts, especially bis (amidino) ether salts, carboxyl-activated hardeners applied in combination with complexing salts, carbamoyl in combination with certain aldehyde scavengers Carbamoylpyridinium and carbamoyloxypyridinium salts, hydroxylamine esters of dicationic ethers, imidates and chloroformamidinium salts, mixed function hardeners such as halogen-substituted aldehyde acids (eg, mucochloric acid and mucobromine) Acids), onium-substituted acrolein, vinyl sulfones containing other hardening functional groups, polymeric hardeners such as dialdehyde starch and copoly (acrolein-methacrylic acid).

The amount of silver contained in each silver halide emulsion unit of the radiographic element is generally from 8 mg / dm ^{2 to} 11 mg / dm ^2.
mg / dm ² or less, preferably 9 mg / dm ² or more and 10
mg / dm ² or less. Further, the coating amount of the gelatin-based vehicle is generally 6 mg / dm ² or more and 11 mg.
/ Dm ² or less, preferably 7.5 mg / dm ² or more.
It is in the range of 5 mg / dm ² or less. The amount of silver and the amount of gelatin-based vehicle may be the same or different on both sides of the support.

The radiographic elements generally include a surface overcoat typically provided on each side of the support to physically protect the emulsion layers. In addition to the vehicle features described above, the overcoat can contain various additives to modify its physical properties. Such additives can be found in Research Disclosure (Resea
rch Disclosure, Item 36544) section IX. Coati
ng physical propertymodifying addenda, A. Coating
aids, B. Plasticizers and lubricants, C. Antistats,
and D. Matting agents. An intermediate layer, typically a thin hydrophilic colloid layer, can be used to separate the emulsion layer and the surface overcoat. It is quite common to place in the interlayer a surface overcoat additive of a type compatible with the emulsion, such as anti-matte particles.

The treatment method of the present invention is advantageous because it can be carried out using a treatment kit containing some or all of the treatment compositions required for the method. The processing kit includes, as a minimum, the black-and-white developing / fixing monobath composition of the present invention, a processing container, a black-and-white photographic silver halide element (one or more samples thereof), instructions for use, a washing solution,
One or more other components, such as a fluid or composition metering device, or any other components commonly used in photographic processing kits, may also be included. All components can be suitably packaged in dry or liquid form in glass or plastic bottles, fluid impermeable packets or vials.

[0054]

The following examples are for illustrative purposes and do not limit the invention in any way. Materials and Methods for Examples Radiographic films (Element A) of the present invention were prepared having the following layer arrangement and composition on each side of a poly (ethylene terephthalate) support. Overcoat composition Coverage (mg / dm ² ) Gelatin vehicle 3.4 Methyl methacrylate mat beads 0.14 Carboxymethyl casein 0.57 Colloidal silica 0.57 Polyacrylamide 0.57 Chrom alum 0.025 Resorcinol 0.058 Whale oil reduced Lubricant 0.15

Intermediate Layer Composition Coverage (mg / dm ² ) Gelatin Vehicle 3.4 AgI Lippmann Emulsion (0.08 μm) 0.11 Carboxymethylcasein 0.57 Colloidal Silica 0.57 Polyacrylamide 0.57 Chrom Alum 0.025 Resorcinol 0.058 Nitron 0.044

Emulsion composition Coating amount (mg / dm ² ) T-grain emulsion (AgBr 2.0 × 0.07 μm) 10.6 Gelatin 7.5 4-hydroxy-6-methyl-1,3,3a, 7-tetraazaindene 2.1 g / Ag mol 4-hydroxy-6-methyl-2-methyl mercapto-1,3,3a, 7-tetraazaindene 400 mg / Ag mol 2-mercapto-1,3-benzothiazole 30 mg / Ag Molar potassium nitrate 1.8 Ammonium hexachloropalladate 0.0022 Maleic hydrazide 0.0087 Sorbitol 0.53 Glycerin 0.57 Potassium bromide 0.14 Resorcinol 0.44 Dextran P 2.5 Polyacrylamide 2.69 Carboxymethyl casein 1 .61 bisvinylsulfonyl methyl ether 0.4% of the total amount of gelatin in all layers

A control radiographic element (Element B) was also evaluated using the compositions and methods of the present invention. The control element is commercially available as KODAK T-MAT G radiographic film. In Examples 1 to 5, the following Table I
The developing / fixing composition described in II was used. Sodium hydroxide was added to adjust the pH of each solution, but other suitable bases can be used for this purpose.

[0058]

[Table 3]

Examples 1-5 To determine the performance of various developing / fixing compositions of the present invention containing various amounts of ascorbic acid and cysteine,
These examples were used. Control monobass compositions outside the scope of the invention were also tested. These compositions were used to generate images on the samples of radiographic elements A and B described above. After exposing the sample of the above element with a fluorescent lamp of 500 lux for 60 seconds,
Each of the developing / fixing monobath compositions shown in Table IV below was processed at room temperature and under room light. The results of various sensitometric measurements (fog, Dmax, dynamic range) shown in Table IV have a general meaning and are measured by a common method.

[0060]

[Table 4]

These results are used when processing element B:
This shows that incomplete fusing (high fog) also occurs, which also causes a higher _Dmax . Conversely, Element A using the develop / fix monobass compositions of Examples 1-5 of the present invention gave acceptable sensitometric results. The present invention generally gave comparable or better dynamic ranges (higher values are better) with less fog.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03C 1/74 G03C 1/74 5/26 510 5/26 510 5/30 5/30 5/305 5 / 305 5/38 5/38

Claims (3)

[Claims] 1. It has a pH of 10 to 12.5, is free of dihydroxybenzene developing agent and ammonium ions, and has a pH of 80 mmol / L to 200 mmol /
Aqueous solution comprising ascorbic acid developing agent of L, at least 200 mmol / L of sulfite ion, and 40 mmol / L to 300 mmol / L of an organic compound having both thiol group and amino group as a sole photographic fixing agent Black-and-white developing / fixing monobass composition. 2. A method for providing a black and white image comprising the step of contacting an imagewise exposed black and white photographic silver halide element with the aqueous black and white developing / fixing monobass composition of claim 1. The method is performed within a maximum of 180 seconds, and prior to the contacting step, the black-and-white photographic silver halide element comprises, on each side of its support, a silver halide comprising silver halide grains and a gelatin-based vehicle. An emulsion unit is provided, and the silver halide grains are composed of bromide in an amount of 95 mol% or more based on the total silver, and 50% or more of the projected area of the silver halide grains has an average aspect ratio. 8
Higher, occupied by tabular grains having a thickness of less than 0.10 μm and an average grain size in the range of 1.5 to 3 μm, the silver coverage in each silver halide emulsion unit being 11
mg / dm ² or less, and the coverage of the gelatin-based vehicle in each silver halide emulsion unit was 11 mg.
/ Dm ² or less. 3. A) having a pH of 10 to 12.5, containing no dihydroxybenzene developing agent and ammonium ions, and from 200 mmol / L to 500 mmol / L of ascorbic acid developing agent, at least 200 mmol / L Black-and-white developing / fixing monobass composition comprising, as a sole photographic fixing agent, 40 to 300 mmol / L of an organic compound having both a thiol group and an amino group, and b) each surface A support on which a silver halide emulsion unit containing silver halide grains and a gelatin-based vehicle is disposed, wherein the silver halide grains are composed of bromide in an amount of 95 mol% or more based on the total silver. 50% or more of the projected area of the silver halide grains has an average aspect ratio higher than 8 and a thickness of 0.10 μm or less. By and and average particle size is occupied by tabular grains in the range of 1.5～3Myuemu, coverage of silver in each silver halide emulsion unit 11
mg / dm ² or less, and the coverage of the gelatin-based vehicle in each silver halide emulsion unit was 11 mg.
A processing kit comprising a black-and-white photographic silver halide element having a density of / dm ² or less.